Coal-drill.



PATENTED FEB. 19, 1907.

J. KATULKA.

GOAL DRILL.

APPLICATION FILED NOV. so, 1906.

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L M/ 7C inform n'nrra' .s'raras EfaENT @FFICE.

JOHN KATULKA, OF )NANTICOKE, PENNSYLVANIA. COAL-DRILL.

Specification of Letters Patent.

Patented ab. 19, 1907.

Application filed November 30,1908- Serial No. 345.703.

To all whom, it may concern:

Be-it known that I, JOHN KATULKA, a citizen of the United States, residing at N anticoke, Luzerne county, State of Pennsylva- In the accompanying drawings, Figure 1 is w an "elevation of acoal-mining 15.

vention. Fig. 2 is a. view of the cuttingdrill constructed in accordance with the present inhead detached from the stem or body of the drill and viewed in a direction substantially at right angles to the side exposed in Fig. 1. Fig. 3 illustrates the form of bore made by the im roved drill.

efe'rring to the drawings, the stem or bodyof the drill 1 is provided with ribs or flanges,

shorter auxiliary cutter 6.

which form a spiral way or passage extending longitudinally of the stern, b means of which the cuttings produced by t iecuttinghead, hereinafter described, will be removed from the bore produced by rotating the drill, and thus prevent clogging or obstruction of the cutting edges. l

' At one end the stem 1 is provided with a suitable socket, preferably polygonal in cross-section, adapted to, receive, a correspondingly-shaped stud or pin on the cutting-head. The latter comprises a central or main cutter'2, made in the form .of an auger and having its free end split to provide two oppositely-curved cutting-points 3 4 and. a pair of auxiliary or supplemental cutters 5 6, which are arranged on opposite sides of and extend longitudinally of the central cutter 2. Said parts 2 5 6 are formed integral and preferably' of soft steel. 5 6 are of different lengths, and the point or free end of the cutter 5 is relatively closer to the central auger-like cutter 2 than the other The inner edge of the auxiliary cutter 5 is in substantially the same longitudinal plane as the-outer end of the cutting-point 3, and the inner edge of the cutter 6 is substantially at the same distance from the axis of the central auger-like cutter 2 as the outer edge of the other auxiliary cutter 5.

The polygonal shank or stud 7 on the cutting-head is of such size and form as to fit The auxiliary cutters closely in the socket in the stem 1 and may be held therein .b a key 9, extending through a notch 8, forme in said shank.

It will be 'seen that thecentral auger-like cutter projects some distance beyond the points of the auxiliary cutters 5 6, which, as above noted, are of different lengths, and therefore in operation said central cutter will form a relatively small pocket 10, while the auxiliary cutters 5 6 will respectively form cuttings 11 12, the latter being of'substantially the same diameter as the stem 1. By this construction the central cutter 2 acts .to securely support and guide the auxiliary cutters 5 6, which rapidly enlarge the passage formed by the cutting-points 3 4 to the full diameter of the drill.

By forming all of the cutters from a single piece and emplo 'ng soft steel it is possible to provide a very d iirable bit, and by arranging the respective cutters .in the manner illustrated and described the drill may be oper,

ated by a minimum amount of power.

Having thus described the invention, what is claimed, and desired to be secured by Letters Patent, is

1. The herein-described coal-drill comprising a stem provided with ribs forming a spiral way or passage about the stem, a con trally-arranged auger-like cutter at one end of said; stem, and two auxiliary cutters of different lengths, formed integral with and arranged on opposite sides of said main cutter,

the longer auxiliary cutter having its cutting edge closer to the main cutter than the other. shorter, auxiliary cutter, substantially as and for the'pur ose described.

2. The aerein-described coal-drill comprising a spirally-grooved stem, and a cutting-head det'aehably connected with said stem and including-a central auger-like (11tter, terminating in two oppositely-curved cutting-points, and two auxiliary cutters extending longitudinally of and arranged on opposite sides of said central cutter, said auxiliary cutters being curved longitudinall and of different lengths, and the longer one eing arranged closer to the central cutter than the other, shorter, one.

In testimony whereof I aflix my signature in presence of two witnesses.

JOHN .KATULKA.

Witnesses:

W. L. RAEDER, K. E. FERRY. 

